wow this thread is all over the place.
FINAL WORD: ***ANY*** steroid has the capacity to cause hairloss in users, including anavar, primo and every single other one. the manifestation varies a great deal among users, and yes androgenic potency MAY be a predictor, but it is far from 100% accurate. also, 5A-reduced steroids like primo and var (and 1-T. M1T, tren, masteron, proviron, MDHT, etc etc) seem to be a bit worse than non-5A-reduced ones, but that's not always true either. plenty of guys have lost hair on dbol (it may be argued that it's due to its reduction to M1T analogues, but anyway...)
you're going to have to experiment and see what happens.
my personal experience is that shorter cycles produce less permanent hairloss, and stronger steroids cause hairloss more often than weaker ones (thus the myth that primo and anavar are easy on hairlines - they are pretty weak, but at high doses they can be brutal. ask around.)